CECOAL   02625
CENTRO DE ECOLOGIA APLICADA DEL LITORAL
Unidad Ejecutora - UE
artículos
Título:
Un nuevo tallo permineralizado de Equisetales de la Formación Los Rastros (Triásico Medio - Superior), provincia de San Juan, Argentina
Autor/es:
CRISAFULLI, A Y LUTZ A
Revista:
Revista del Museo Argentino de Ciencias Naturales n.s.
Editorial:
Museo Argentino de Ciencias Naturales Bernardino Rivadavia
Referencias:
Lugar: Buenos Aires; Año: 2008 vol. 10 p. 71 - 79
Resumen:
Abstract: A new permineralized Equisetalean stem from Los Rastros Formation (Middle-Upper Triassic) from San Juan province, Argentina. Several stems remains of a new genus and species belonging to the order Equisetales are described. They are represented by ribbed stems with distinct nodes and internodes, a pith with some sclerenchymatic cells and carinal canals. Wedge-shaped primary xylem and fascicular wedges of secondary xylem alternating with uniseriate rays are preserved. Comparison of these stems with other Equisetalean fossils from Gondwana is difficult because of their different kinds of preservation. There are only few records of permineralized Equisetalean stems from the Gondwana Triassic because the majority of data are derived from compression-impression fossils; however, one of them, Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. the order Equisetales are described. They are represented by ribbed stems with distinct nodes and internodes, a pith with some sclerenchymatic cells and carinal canals. Wedge-shaped primary xylem and fascicular wedges of secondary xylem alternating with uniseriate rays are preserved. Comparison of these stems with other Equisetalean fossils from Gondwana is difficult because of their different kinds of preservation. There are only few records of permineralized Equisetalean stems from the Gondwana Triassic because the majority of data are derived from compression-impression fossils; however, one of them, Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. the order Equisetales are described. They are represented by ribbed stems with distinct nodes and internodes, a pith with some sclerenchymatic cells and carinal canals. Wedge-shaped primary xylem and fascicular wedges of secondary xylem alternating with uniseriate rays are preserved. Comparison of these stems with other Equisetalean fossils from Gondwana is difficult because of their different kinds of preservation. There are only few records of permineralized Equisetalean stems from the Gondwana Triassic because the majority of data are derived from compression-impression fossils; however, one of them, Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. the order Equisetales are described. They are represented by ribbed stems with distinct nodes and internodes, a pith with some sclerenchymatic cells and carinal canals. Wedge-shaped primary xylem and fascicular wedges of secondary xylem alternating with uniseriate rays are preserved. Comparison of these stems with other Equisetalean fossils from Gondwana is difficult because of their different kinds of preservation. There are only few records of permineralized Equisetalean stems from the Gondwana Triassic because the majority of data are derived from compression-impression fossils; however, one of them, Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. Several stems remains of a new genus and species belonging to the order Equisetales are described. They are represented by ribbed stems with distinct nodes and internodes, a pith with some sclerenchymatic cells and carinal canals. Wedge-shaped primary xylem and fascicular wedges of secondary xylem alternating with uniseriate rays are preserved. Comparison of these stems with other Equisetalean fossils from Gondwana is difficult because of their different kinds of preservation. There are only few records of permineralized Equisetalean stems from the Gondwana Triassic because the majority of data are derived from compression-impression fossils; however, one of them, Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species. Spaciinodum Osborn & Taylor, from Antarctica, is also based on a permineralization. The anatomical structure of the studied material suggests that it is a new taxon, as their features differ from all previously known species.